Controller task types
Tasks are the most configurable organization unit and are at the trunk of a Logix project. They provide a means of optimizing the execution of our project. It is important to remember that the Logix controllers are only capable of running one task at a time. However, tasks can interrupt the execution of other tasks if they are triggered and have a higher priority value. Tasks that are interrupted will start again where they left off in the execution of their code.
Note
It is important to keep in mind that other tasks can change the data your routine's code is executing on. Care should be taken to buffer tags in order to avoid the code from entering a state that was not accounted for. Buffering has been covered in detail in Chapter 5, Writing Ladder Logic.
There are three types of tasks in Studio 5000 Logix Designer (RsLogix 5000):
Continuous
Periodic
Event
Continuous tasks
Continuous tasks will execute as quickly as they can and will always be running on the controller when...